| | Re: Hidden surface removal, and vertex order in part/primitive DAT files
|
|
(...) I guess we could at least decide to use CCW to determine the normal of a face, unless there's someone who prefers to use CW ? Leonardo (25 years ago, 1-Oct-99, to lugnet.cad.dev)
|
|
| | Re: CW/CCW, vertex sequence, co-planar, convex, (115kB)
|
|
(...) If we know that a face is CW, why not change it to CCW ? The most difficult task is to discover the orientation of a face, but once we have that information anyone can change the order of the points and fix the face. (...) This can be done (...) (25 years ago, 1-Oct-99, to lugnet.cad.dev)
|
|
| | Re: CW/CCW, vertex sequence, co-planar, convex, (115kB)
|
|
Lars C. Hassing wrote in message <938787015.279086@ns.cci.dk>... (...) of (...) we will (...) Hold on. Why not just have a button in the CAD program to turn the part inside-out by automatically manipulating the orientation matrix in the parent dat (...) (25 years ago, 1-Oct-99, to lugnet.cad.dev)
|
|
| | Re: CW/CCW, vertex sequence, co-planar, convex, (115kB)
|
|
Steve Bliss wrote in message <37f4ab7d.64002272@l...et.com>... (...) Doh'! You're right. (...) I'm having a difficult time picturing in my mind how an asymmetrical part can have its orientation matrix in the parent dat file mirrored and rotated (to (...) (25 years ago, 1-Oct-99, to lugnet.cad.dev)
|
|
| | Re: CW/CCW, vertex sequence, co-planar, convex, (115kB)
|
|
Jacob Sparre Andersen <sparre@sys-323.risoe.dk> wrote in message news:FIxHC0.E2v@lugnet.com... (...) I'm not so sure about this anymore. I think the ideal would be a program that could change the part files so that they are completely CCW. Using (...) (25 years ago, 1-Oct-99, to lugnet.cad.dev)
|
|
| | Re: CW/CCW, vertex sequence, co-planar, convex, (115kB) [DAT]
|
|
Lars: (...) [...] (...) This would demand a lot of work before people could start using programs that use this fact. (...) Right. (...) Just check the determinant of the rotation matrix (but you know that I suppose). (...) I would rather use some (...) (25 years ago, 1-Oct-99, to lugnet.cad.dev)
|
|
| | Re: CW/CCW, vertex sequence, co-planar, convex, (115kB) [DAT]
|
|
Leonardo Zide wrote in message <37F383E1.CA6B8962@c...com.br>... (...) I agree with John Van in that we need three keywords: CCW, CW, UNKNOWN. As the rendering program is going to keep track of the number of mirrorings of the transformations (or (...) (25 years ago, 1-Oct-99, to lugnet.cad.dev)
|
|
| | Re: CW/CCW, vertex sequence, co-planar, convex, (115kB)
|
|
(...) It wouldn't matter if they were closed-volume or not--they could still be turned inside out accidently. And an inside-out closed-volume primitive wouldn't do anybody any good. (...) Why? Steve (25 years ago, 1-Oct-99, to lugnet.cad.dev)
|
|
| | Re: Hidden surface removal, and vertex order in part/primitive DAT files
|
|
(...) I'm willing to change my parts, if the standard changes. Assuming parts which are *not* C(C)W need to be flagged at all. (...) I agree completely. Steve (25 years ago, 1-Oct-99, to lugnet.cad.dev)
|
|
| | New Group Idea
|
|
We should have a lugnet.cad.dat.clones group, now that someone over on RTL is doing megablocks parts. bThe group would be expressly for posting clone lego parts, official sets and MOC's. -- Jonathan Wilson wilsonj@xoommail.com (URL) (25 years ago, 1-Oct-99, to lugnet.cad.dev)
|